migrants from nearby burma are the lifeblood of the thai shrimp industry. most thais wont work for the low wages paid by the shrimp producers. today as many as 400,000 burmese migrants work in samut sakhon, where 40% of thailand's shrimp are peeled and frozen for export. only 70,000 workers are lelly registered. >> there are an estimated 1,200- 1,300 factories. 300-400 of which are not registered with the government. >> reporter: thai labor activist sampong sakaew says the most severe abuses occur in the network of unregistered, almost invisible, peeling sheds that supply shrimp to larger factories for export to the u.s. >> the small factory owners know that most of their workers are undocumented, so they can control the work force however they want; such as locking workers in until they finish their work. there arelso teenagers between 12-17 years old in the work force. >> ( translated ): we were made to work from 3:00 a.m. until 9:00 p.m. we earned about $6 a day. our hands were like machines. >> reporter: like most migrants, ko ngwe htay was eager to lea